21/01/2017 12:30 v Liverpool
The Swans claimed a first ever league victory at Anfield following an action-packed 3-2 win over Liverpool.
After a goalless first half, the second period was full of drama, chances and five goals as head coach Paul Clement saluted his first victory since taking over the job.
Fernando Llorente's brace gave the Swans a 2-0 lead after 52 minutes, which stunned Anfield into silence.
But back came Liverpool, with Roberto Firmino scoring two of his own as Jurgen Klopp's side drew themselves level.
The Swans, though, were not done there as Sigurdsson took advantage as he got onto the end of a loose ball to slot home after 74 minutes.
That wasn't job done for the Swans though, with Lukasz Fabianski making some fine saves and heroic defending holding off Liverpool's late efforts to take something from the game.
Victory moved the Swans out of the relegation zone - ahead of the afternoon's remaining games - with 18 points from 22 games, while this was Liverpool's first defeat at Anfield in over a year.
New signings Martin Olsson and Tom Carroll both made their debuts.
The Swans' latest acquisitions - who both arrived on Tuesday - started as part of three changes from the side that was beaten by Arsenal last time out.
Olsson got the nod at left-back while Carroll - making his second debut following a loan spell in 2014-15 - was part of a midfield which also included Leroy Fer.
The Swans set up to soak up the early Liverpool pressure at Anfield, and they did just that for the opening 45 minutes.
The Reds were in total control of possession and territorial advantage, and they first went close in the 13th minute as Emre Can headed wide from 12 yards.
It was a warning sign, with Jurgen Klopp's side continually probing but the Swans were defending astutely.
Adam Lallana wasted another fine chance to break the deadlock as his overhead kick flew over following Roberto Firmino's cross.
The Swans, remaining compact, briefly broke into the final third, and they went within inches of opening the scoring after Gylfi Sigurdsson sent Tom Carroll into the box, but his shot deflected off Dejan Lovren and out for a corner via the near post.
It was a sign of the visitors' threat, but it was only a rare moment of worry for Liverpool.
The brave defending continued for Paul Clement's side, with Alfie Mawson throwing himself in front of Firmino's shot to deflect it wide for a corner.
That was the type of defending the Swans needed, and their efforts were enough to enter the break on level terms.
If the first half was tight and compact, the second half was the exact opposite.
Just three minutes had gone when the Swans stunned Anfield.
Sigurdsson's corner was nodded goalwards by Federico Fernandez, and when it deflected off Routledge's feet to Fernando Llorente, the big Spaniard poked home from three yards.
If that was good, things got even better.
With just 52 minutes on the clock, the home crowd were stunned into silence.
Olsson flicked a pass for Carroll, his powerful cross was nodded home by Llorente.
It was a stunning start, but Liverpool wouldn't take long to reply.
Just three minutes later, James Milner's cross found Firmino, and he leapt above Olsson to head past Lukasz Fabianski.
It was thrilling stuff, and far more was to come.
At the other end, another Sigurdsson corner was met this time by Mawson, and his header dropped just wide.
Liverpool were full of energy though, and they were back on level terms just before the hour mark.
Another cross, this time from Georginio Wijnaldum, met Firmino, and he chested down before volleying home.
It could have knocked the stuffing out of Clement's side, but they kept their heads up.
And, in this bizarre half, they retook the lead just five minutes after being pegged back.
The lively Carroll surged towards the box, and when the ball was touched wide to Sigurdsson, he slotted home from close range.
The chaos continued, with hearts in mouths.
Lallana headed over a frantic melee in the box which almost saw Jack Cork's header drop into his own net.
Five minutes of added time followed.
Fortunately, the Swans held out for a massive three points.
LIVERPOOL: Simon Mignolet, Nathaniel Clyne, Georginio Wijnaldum (Joel Matip, 90), Dejan Lovren, James Milner, Philippe Coutinho (Daniel Sturridge, 57), Roberto Firmino, Jordan Henderson (capt), Ragnar Klavan, Adam Lallana, Emre Can (Divock Origi, 70).
SUBS: Loris Karius, Alberto Moreno, Lucas, Ben Woodburn.
SWANS: Lukasz Fabianski, Kyle Naughton, Federico Fernandez, Alfie Mawson, Martin Olsson (Angel Rangel, 79), Jack Cork (capt), Tom Carroll, Leroy Fer (Jay Fulton, 90), Wayne Routledge, Gylfi Sigurdsson, Fernando Llorente (Borja, 85).
SUBS: Kristoffer Nordfeldt, Jordi Amat, Nathan Dyer, Oli McBurnie.